Feeding bacteria seaweed to make compostable plastic

Patricia Maia Noronha is a freelance writer in Lisbon, Portugal.

You can also search for this author in PubMed Google Scholar

Jesús E. Rodríguez is a bioprocess engineer at ULUU in Watermans Bay, Australia. Credit: Giacomo d’Orlando for Nature

You have full access to this article via your institution.

My team and I make bioplastics from simple renewable ingredients: saltwater microbes, seaweed and seawater. The seaweed provides a carbon source for fermentation, similar to how beer is made by fermenting hops. The saltwater microbes naturally produce polymers called polyhydroxyalkanoates (PHAs) that could replace many, maybe even all, synthetic plastics. And these PHAs are biodegradable, even in cold, dark conditions such as the deep ocean. Unlike other bioplastics, this material will also compost on its own in household waste.

In this photo, from May 2023 in my laboratory at ULUU, a biotechnology company in Watermans Bay, Australia, I am adding a seawater solution to a colony of bacteria. The salt water causes the cells to explode, releasing PHAs into the solution. ULUU aims to replace all synthetic plastics with biopolymers.

I took a winding path to get here. I studied agro-industrial engineering at the Lisandro Alvarado Central Western University in Barquisimeto, Venezuela, my home country. In my last semester, which I did at the University of Padua, Italy, I used fermentation to produce bioethanol, a renewable-energy source. I did my PhD there, then postdoctoral research at the University of Verona, Italy, focusing on microbial production of PHAs. I joined ULUU last August.

Most PHA producers use glucose from maize corn or sugar cane. Seaweed is advantageous because it grows quickly and cheaply, and we don’t have to remove it from the global food supply.

Our bioplastics are being tested for use in buttons and containers. We want to offer alternatives for any industry that uses plastic, from packaging to stationery. Our latest creation is a fibre for textiles.

ULUU is a multicultural team of 16 people from around the world. We share a common vision: a world where plastics come from bacteria, not chemical factories.

Nature 620, 460 (2023)

doi: https://doi.org/10.1038/d41586-023-02499-4

Read the paper: Ranching sea cucumbers to repair the oceans – and improve human health

Why I’m a garbage collector for the world’s oceans

Building a living shoreline to help combat climate change

Careers advice from scientists in industry

Waiting on tables, mending puppets: the first jobs that shaped researchers’ careers

Career Feature 28 AUG 23

‘Gagged and blindsided’: how an allegation of research misconduct affected our lab

Career Feature 25 AUG 23

Leveraging my training in space medicine for technological innovation

Career Q&A 22 AUG 23

Analog chip paves the way for sustainable AI

News & Views 23 AUG 23

Brain implants that enable speech pass performance milestones

News & Views 23 AUG 23

An analog-AI chip for energy-efficient speech recognition and transcription

Article 23 AUG 23

Entropic repulsion of cholesterol-containing layers counteracts bioadhesion

Article 21 JUN 23

Cartilage-like protein hydrogels engineered via entanglement

Article 21 JUN 23

Hydration solids

Article 07 JUN 23

Scripps Research, Dept of Molecular & Cellular Biology, is seeking outstanding applicants for a tenure track faculty position in La Jolla, CA.

La Jolla, California

Scripps Research Institute

Scripps Research, Dept of Integrative Structural & Computational Biology, is seeking outstanding applicants for a tenure track faculty position.

La Jolla, California

Scripps Research Institute

An Associate Specialist position is available in the Immunogenetics and Transplantation Laboratory (ITL, https://itl.ucsf.edu/) at the UCSF

San Francisco, California

University of California San Francisco

Houston, Texas (US)

Baylor College of Medicine (BCM)

Houston, Texas (US)

Baylor College of Medicine (BCM)